Backlight unit and display device

Abstract

A backlight unit and a display device includes a plurality of light sources and a color conversion layer on a reflective layer, thereby removing expensive color conversion sheets and supplying high-quality white light. A backlight unit includes a printed circuit; light sources on the printed circuit; a reflective layer on at least a partial area of an area in which the light sources are not disposed on the printed circuit; a transparent film above the light sources and the reflective layer and spaced apart from the light sources and the reflective layer; light diffusion patterns on at least one of the top and bottom of the transparent film and corresponding to each of the light sources; a first color conversion layer on the reflective layer; and a second color conversion layer on at least one of a top surface and a bottom surface of the light diffusion patterns.

What is claimed is: 
     
       1. A backlight unit, comprising:
 a printed circuit; 
 a plurality of light sources disposed on the printed circuit; 
 a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit; 
 a transparent film disposed above the plurality of light sources and the reflective layer and spaced apart from the plurality of light sources and the reflective layer; 
 a plurality of light diffusion patterns disposed on at least one of the top and bottom of the transparent film and corresponding to each of the plurality of light sources; 
 a first color conversion layer disposed on the reflective layer; 
 a second color conversion layer disposed on at least one of a top surface and a bottom surface of the plurality of light diffusion patterns; and 
 wherein each of the plurality of light sources is disposed inside a hole in which the reflective layer is not disposed on the printed circuit, 
 wherein the first color conversion layer having a pattern surrounding the hole, 
 wherein the pattern is a radial dot pattern centered on the light source, and 
 wherein a size of the dot close to the hole is larger than a size of the dot far from the hole. 
 
     
     
       2. The backlight unit of  claim 1 , wherein the pattern of the first color conversion layer is a pattern comprising two or more rings surrounding the hole, and
 at least a portion of the reflective layer is exposed between the two or more rings, and a width of a ring close to the hole is greater than a width of a ring far from the hole. 
 
     
     
       3. The backlight unit of  claim 1 , wherein the second color conversion layer comprises a center pattern filled inside and a peripheral pattern surrounding the center pattern. 
     
     
       4. The backlight unit of  claim 3 , wherein the peripheral pattern is a ring pattern surrounding the center pattern. 
     
     
       5. The backlight unit of  claim 3 , wherein the peripheral pattern is a pattern comprising a plurality of dots surrounding the center pattern, and
 the size of each of the plurality of dots is smaller than the size of the center pattern. 
 
     
     
       6. The backlight unit of  claim 1 , wherein the first color conversion layer comprises: a plurality of phosphors that are excited by light emitted from the plurality of light sources to emit light of different wavelengths; and a resin in which the plurality of phosphors are mixed, and
 the first color conversion layer is patterned on the reflective layer. 
 
     
     
       7. The backlight unit of  claim 1 , wherein the second color conversion layer comprises: a plurality of phosphors that are excited by light emitted from the plurality of light sources to emit light of different wavelengths; and a resin in which the plurality of phosphors are mixed, and
 the second color conversion layer is patterned on at least one of the plurality of light diffusion patterns and a top surface and a bottom surface of the transparent film. 
 
     
     
       8. A backlight unit comprising:
 a printed circuit; 
 a plurality of light sources disposed on the printed circuit; 
 a transparent film disposed above the plurality of light sources and spaced apart from the plurality of light sources; 
 a plurality of light diffusion patterns disposed on at least one of the top and bottom of the transparent film and corresponding to each of the plurality of light sources; 
 a first color conversion layer disposed on at least a partial area among an area at which the plurality of light sources are not disposed; 
 a second color conversion layer disposed on at least one of a top surface and a bottom surface of the plurality of light diffusion patterns; and 
 wherein the backlight unit further comprises a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit, 
 wherein the transparent film is disposed on the reflective layer and spaced apart from the reflective layer, 
 wherein the first color conversion layer is disposed on the reflective layer, 
 wherein each of the plurality of light sources is disposed inside a hole in which the reflective layer is not disposed on the printed circuit, 
 wherein the first color conversion layer having a pattern surrounding the hole, 
 wherein the pattern is a radial dot pattern centered on the light source, and 
 wherein a size of the dot close to the hole is larger than a size of the dot far from the hole. 
 
     
     
       9. A display device comprising:
 a display panel; and 
 a backlight unit to supply light to the display panel, 
 wherein the backlight unit comprises 
 a printed circuit, 
 a plurality of light sources disposed on the printed circuit, 
 a transparent film disposed on the plurality of light sources and spaced apart from the plurality of light sources, 
 a plurality of light diffusion patterns disposed on at least one of the top and bottom of the transparent film and corresponding to each of the plurality of light sources, 
 a first color conversion layer disposed on at least a partial area among an area at which the plurality of light sources are not disposed, and 
 a second color conversion layer disposed on at least one of a top surface and a bottom surface of the plurality of light diffusion patterns, 
 wherein the backlight unit further comprises a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit, 
 wherein the transparent film is disposed on the reflective layer and spaced apart from the reflective layer, 
 wherein the first color conversion layer is disposed on the reflective layer, 
 
       wherein the second color conversion layer comprises a center pattern filled inside and a peripheral pattern surrounding the center pattern. 
     
     
       10. The display device of  claim 9 , wherein each of the plurality of light sources is disposed inside a hole in which the reflective layer is not disposed on the printed circuit, and
 the first color conversion layer having a pattern surrounding the hole. 
 
     
     
       11. The display device of  claim 10 , wherein the pattern of the first color conversion layer is a pattern comprising two or more rings surrounding the hole, and
 at least a portion of the reflective layer is exposed between the two or more rings, and a width of a ring close to the hole is greater than a width of a ring far from the hole. 
 
     
     
       12. The display device of  claim 10 , wherein the pattern is a radial dot pattern centered on the light source, and
 a size of the dot close to the hole is larger than a size of the dot far from the hole. 
 
     
     
       13. The display device of  claim 9 , wherein the peripheral pattern is a ring pattern surrounding the center pattern. 
     
     
       14. The display device of  claim 9 , wherein the peripheral pattern is a pattern comprising a plurality of dots surrounding the center pattern, and
 the size of each of the plurality of dots is smaller than the size of the center pattern. 
 
     
     
       15. The display device of  claim 9 , wherein the first color conversion layer comprises: a plurality of phosphors that are excited by light emitted from the plurality of light sources to emit light of different wavelengths; and a resin in which the plurality of phosphors are mixed, and
 the first color conversion layer is patterned on the reflective layer. 
 
     
     
       16. The display device of  claim 9 , wherein the second color conversion layer comprises: a plurality of phosphors that are excited by light emitted from the plurality of light sources to emit light of different wavelengths; and a resin in which the plurality of phosphors are mixed, and
 the second color conversion layer is patterned on at least one of the plurality of light diffusion patterns and a top surface and a bottom surface of the transparent film.